Thanks for the reply. I'd thought of that, but it removes the utility of the system. My laptop is the "source", and as a laptop is only transiently switched on during the day. I want to take advantage of any up time to sync. What I don't understand is what exactly the btsync on the "destination" is *doing*. The source is not online, consequently there are no seeds to download from. Why is it checking the destination files? I suspect that in the absence of a stylish way of sorting this out ill just have a script that continually checks to see if the laptop is online, and when it drops off the network then terminates the btsync process, restarting it upon spying the laptop on the network. That will unfortunately require another forum to post newbie questions in as I learn to write the script!